1. Field of the Invention
The invention relates generally to repair of memory by redundancy. The invention relates more specifically to a method of reducing power consumption in a memory having a redundancy-based repair system.
2. Description of the Related Art
High density memory devices typically include a redundancy-based repair system for substituting redundant rows or columns of memory cells for use in place of non-operational or defective primary rows or columns.
When a defective primary row or column (hereafter, primary memory block) is detected within a memory device, the row or column addressing mechanism of the device is reprogrammed to select an operative redundant memory block in place of the defective primary block.
This reprogramming or "select-substituting" step works by disabling all requested couplings of the local data read and/or data write lines of the defective memory block to the global read and/or write lines of the memory device. The select-substituting step also enables a substitute coupling of the local data read and/or write lines of the redundant memory block to the global read and/or write lines of the memory device in response to access requests directed at the defective memory block. Data which would have been stored in or read from the defective primary block is instead written to or fetched from the redundant memory block.